Use of netcat Tools

Purpose: Network management tools.

Can read, write TCP or UDP network connections. Abbreviated as: NC

Common parameters:

-H Help Information

-L firm Mode

-N Specify IP address

-P Specify port number

-V Verbose output

1 Client: It is easy to establish a client/server model.

Eg: $NC-l 1234

NC now listens on port 1234 for connection.

$ NC 127.0.0.1 1234

A connection is established between two ports. Once connected, a conversation can be made between two machines

2 data transfer

NC-L 1234 > Filename.out//Monitor the 1234 port of this machine, wait for file transfer, save as file: Filename.out

Another machine:

NC IP (IP of the previous machine) 1234 < filename.in

When the transfer is complete, the connection is automatically disconnected

3-Port Scan

-Z Means reporting open ports

Nc-z host.example.com 20-30

Port limit between 20-30 ports

HTTP://LINUX.DIE.NET/MAN/1/NC Documentation

Use of netcat Tools